Panel latching arrangement



April 5, 1966 R. s. ARBOGAST 3,244,442

PANEL LATCHING ARRANGEMENT Filed Oct. 21, 1963 1 3%: 42 2,, \Z l [I 3/63 4% \1 i INVENTOR.

ROBERT G. ARBOGAST ATTORNEY United States Patent 3,244,442 PANEL LATCHING ARRANGEMENT Robert G. Arbogast, Bar-stow, Ill., assignor to American Air Filter Company, Inc., Louisville, Ky., a corporation of Delaware Filed Oct. 21, 1963, Ser. No. 317,472 6 Claims. (Cl. 292212) This invention relates to a panel latching arrangement.

Among the objects of the invention is the provision of a latch arrangement made of simple, inexpensive parts and which quite adequately meetsthe requirements of the intended service.

The latching arrangement is well suited for releasably securing a front and top panel assembly to the rear panel of a heating cabinet. The invention will be described primarily in this connection, although it will be appreciated that the arrangement is also well suited for the use in other environments.

A preferred embodiment of the invention will be described in connection with the accompanying drawing, wherein:

FIGURE 1 is a vertical sectional view of a pair of panels secured together with a latching arrangement according to the invention;

FIGURE 2 is an exploded isometric view of the parts of a latch according to the invention; and,

FIGURE 3 is a horizontal sectional view corresponding to one taken along the line 3-3 of FIGURE 1, and including a broken line view showing the latch in a position wherein the panels are released from each other.

In FIGURE 1, the back plate of a heating cabinet is shown mounted against a vertical room wall 12 with the top stub panel 14 of the back plate projecting horizontally away from the wall and terminating in a troughshaped forward margin 16. The rear marginal portion of the cabinet front and top panel assembly is adapted to be releasably secured to the top stub panel 14 with the rear flanged margin 18 of the top panel 26 received by the trough 16 of the back plate forward margin. While only the top panels and a portion of the back plate of the cabinet are shown, it will be understood that the top panel 20 is joined along its forward edge to a vertical front panel (not shown) which extends downwardly and has its lower edge connected by means (also not shown) connecting it to the bottom of the back plate 10. Radiation elements, such as finned tubes, are hung from the back plate 10 in the usual case, and the front and top panels hide the radiation elements from casual view. The top panel 29 is provided with louvered openings (not shown) so that the heated air rising by convection through the interior of the cabinet passes through the louvers in the top panel 20 into the room. v

The means for latching or locking the top panel 20 to the back plate top stub panel 14 is shown in each of the views. Normally one of these latches is provided near each end of the top panel 20, with additional intermediate latches being provided as needed in accordance with the overall length of the cabinet.

The principal parts of the presently preferred latch, perhaps best shown in FIGURE 2, include: a threaded screw or bolt having a shank 22 extending through a hole 24 in the top panel Zil, with the head 26 of the bolt resting on the top surface of the panel 20; a spacer in the form of a hollow right cylinder 28 of nylon on the shank of the bolt; a channel 30 including a web portion 32 and opposite side flanges 34, the channel having an opening 36 provided in the web near one end of the channel to permit the shank of the bolt to freely extend through the hole; and a lock nut 38 into which the threaded shank is turned so as to draw all of the parts of the latch into assembled relation in the above order.

3,244,442 Patented Apr. 5 1966 The channel web 32 is provided with an upstanding tab 40 which is stamped out of the web and serves as a stop which engages a wall of the trough 16 to prevent turning of the channel past a locked position of the latch. Additionally, the end portion of one of the channel flanges 34 is bent out of its normal'vertical plane toward a horizontal plane to form an inclined surface 42 at that corner of the channel which leads or first passes beneath the trough 16 when the channel is swung to a latching position. The purpose of this inclined surface is of course to insure that the latching end of the channel will readily slide under the trough.

As noted, the parts of the latch are assembled in the order shown in FIGURE 2 with the bolt shank 22 first inserted through the hole 24 in the top panel 20, the nylon spacer 28 and channel then being slipped on the shank of the bolt, and lastly the nut 38 is started on the threaded end of the shank. The dimension of the nut 38 across flats is slightly less than the distance between the two channel flanges 34 so that the nut 38 will fit within the channel and be prevented from turning with the bolt if the channel is held stationary. The currently preferred locking nut is of that type which includes a resilient fiber or elastic material insert which substantially increases the friction between the nut and bolt when the bolt is turned to extend completely through the nut.

During assembly of the latch and top panel 20, the bolt is turned relative to the channel and the nut so that the opposite ends of the spacer 28 seat firmly, but not so tightly as to prevent later turning of the bolt with the proper tool, against the underside of the top panel 20 and the top side of the channel web 32, respectively. Since the ends of the spacer cylinder are normal to the axis of the spacer, the channel projects at a right angle from the axis of the bolt shank when the latch is finally assembled. The diameter of the spacer is not critical except that it should be adequate to provide sufiicient area at its ends to maintain the channel in a relatively stable right angle position relative to the shank.

The channel 30 is suificiently long, relative to the placement of the hole 24 in the top panel 20, that at least a part of the web 32 will underlie the trough 16 when the latch is turned to a locking position. The length of the channel should also be suflicient to accommodate the tab stop 40.

When the cabinet top panel 20 is assembled to the remainder of the cabinet at the building site, top panel 20 is fitted to the back plate top stub panel 14, and the bolt is then turned in a clockwise direction (as viewed from the top) so that the channel 30 moves from an unlocked position such as that shown in broken lines in FIGURE 3, to the locked solid line position wherein the channel end underlies the trough 16.

It will be appreciated that as the bolt is turned, the frictional engagement between the bolt and lock nut 38 will result in the channel also turning due to the flat faces of the nut engaging the inside surfaces of the channel flanges 34. Thus the latch will be turned to its locking position wherein the stop 40 engages the wall of the trough as shown in FIGURES 1 and 3. Further turning of the bolt in a clockwise direction will simply increase the compression of the spacer and to the extent that the spacer compresses, increase the frictional engagement of the channel with the trough.

Occasionally during initial assembly of the latch the bolt may not be turned into the nut sufliciently far that the spacer seats firmly on both ends. In this case, when the stop 40 strikes the trough wall during the latching operation the channel and lock nut are prevented from turning while the bolt is turned sufliciently to firmly seat both ends of the spacer 28. It is also noted that the 3 described arrangement lends itself to being tightened to a degree that the possibility of the panels being unlatched accidentally or by unauthorized persons such as children is minimal. In that connection, the slot arrangement in the head 26 of the bolt is preferably of that type adapted to receive a Phillips head screwdriver or some other special tool. This requirement of a special tool coupled with the arrangement which permits the bolt to be turned to a degree that substantial friction must be overcome to turn the bolt in an unlatching direction, virtually insures that the panels will remain latched when so desired.

The arrangement is also such that if the panels are to be released from each other after the latch has tightened to a high degree, the frictional engagement may be readily overcome with the proper tool since the latch will not freeze in this position. Thus, if the channel tends to bind against the trough so that the channel remains in a latched position when the bolt is initially turned in an unlatching direction, the lock nut 38 will then be moved down on the shank of the bolt so that the binding engagement is relieved.

If the installer of the panels turns the bolt in an unlatching direction when he should be turning it in a latching direction the channel will turn counterclockwise (as viewed from the top) until the stop 40 hits the trough, and continued turning of the bolt in this direction will make it apparent to the installer that the latch bolt is loosening rather than tightening. While going through this little misadventure nothing is lost since the lock nut remains on the bolt and the entire latch remains assembled in a somewhat loosened condition. To correct this, the installer needs only reverse the rotation and tighten the bolt after the stop 40 strikes the trough.

Thus in addition to the simplicity and low cost of fabricating a latch arrangement according to the invention, it is essentially fool-proof in its handling and application.

The invention claimed is:

1. A latch assembly for securing a first panel having a trough-shaped margin to a second panel having a down- Wardly flanged margin adapted to be received by said trough, comprising:

(a) a rotatable, threaded member located adjacent said flanged margin of said second panel with its head on the top of said second panel, and the shank of said member extending through said second panel and having mounted thereon in succession;

(b) a substantially rigid spacer element having a length generally corresponding to the depth of said trough;

(c) a locking channel having a hole in its web to receive said shank with the channel projecting at a right angle relative to said shank for a sufiicient distance so as to be laterally displaceable relative the ass-ga e longitudinal axis of said shank to extend under said trough when so directed; and

(d) a lock nut drawn up tightly on said shank between the flanges of said channel, with at least one of said flanges engaging a side face of said nut to prevent relative rotation between said nut and said channel.

2. A latch assembly as specified in claim 1 including:

(a) stop means carried by said channel for engagement against the side of said trough to prevent rotation of said channel past a latching position.

3. The latch assembly of claim 2 wherein:

(a) said stop means comprises a'tab struck upwardly out of said channel web.

4. A latch assembly as specified in claim 1 including:

(a) means forming an inclined plane surface at the end of said channel adapted to be swung under said trough.

5. A latch assembly as specified in claim 4 wherein:

(a) said inclined plane surface comprises an end portion of one of said flanges of said web displaced out of the plane of the rest of the flange.

6. A rotatable latch for securing the edges of adjacent panels having oppositely-directed flanges, comprising:

(a) a rotatable threaded member carried near the flanged edge of one of said panels;

(b) a hollow cylindrical substantially rigid spacer on the shank of said member extending below said pane] and having a length generally corresponding to the depth of said oppositely-directed flanges;

(c) a locking channel on said shank below said spacer. said locking channel having an opening in its web to receive said shank with the channel projecting at a right angle relative to said shank for a sutlicient distance so as to be laterally displacea'ble relative the longitudinal axis of said shank to extend under said oppositely-directed flanges;

(d) a lock nut on said shank below the web of said channel, said lock nut nesting between the flanges of said channel to prevent relative rotation between said nut andsaid channel.

References Cited by the Examiner UNITED STATES PATENTS 1,172,320 2/1916 Tholstrup 292-202 1,357,864 11/1920 Harrington 2922l2 1,433,430 10/1922 Taylor 292'212 1,472,619 10/1923 Starrett 292-56.73 2,795,448 6/1957 Johnson 292216 2,917,267 12/1959 Riddle 292-2l2 X JOSEPH D. SEERS, Primary Examiner.

M. HENSON WOOD, JR., Examiner.

R. E. MOORE, Assistant Examiner. 

6. A ROTATABLE LATCH FOR SECURING THE EDGES OF ADJACENT PANELS HAVING OPPOSITELY-DIRECTED FLANGES, COMPRISING: (A) A ROTATABLE THREADED MEMBER CARRIED NEAR THE FLANGED EDGE OF ONE OF SAID PANELS; 